41 lines
841 B
Swift
41 lines
841 B
Swift
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//
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// WeakArray.swift
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// Tusker
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//
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// Created by Shadowfacts on 3/25/20.
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// Copyright © 2020 Shadowfacts. All rights reserved.
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//
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import Foundation
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fileprivate class WeakWrapper<T: AnyObject> {
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weak var value: T?
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init(_ value: T?) {
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self.value = value
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}
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}
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struct WeakArray<Element: AnyObject>: Collection {
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private var array: [WeakWrapper<Element>]
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var startIndex: Int { array.startIndex }
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var endIndex: Int { array.endIndex }
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init(_ elements: [Element]) {
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array = elements.map { WeakWrapper($0) }
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}
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init(_ elements: [Element?]) {
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array = elements.map { WeakWrapper($0) }
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}
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subscript(_ index: Int) -> Element? {
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return array[index].value
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}
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func index(after i: Int) -> Int {
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return array.index(after: i)
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}
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}
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